Isolation, molecular characterization, and disinfectants susceptibility of swine-carried mammalian orthoreoviruses in Japan in 2020–2022

Abstract

Biosecurity enhancement contributes to the reduction of various microbial pathogens. Mammalian orthoreoviruses (MRVs) which are increasingly recognized as potentially serious problems on swine industry were used as indicators of biosecurity enhancement on two pig farms. Twelve MRVs were detected and isolated from fecal specimens of healthy pigs collected from one of two farms in Japan.By sequencing based on the partial S1 gene, MRV isolates were classified as MRV1 and MRV2.Additionally, the virucidal activities of disinfectants toward the isolated MRV1 were evaluated using quaternary ammonium compound (QAC) diluted 500 times with water (QAC-500), 0.17% food additive glade calcium hydroxide (FdCa(OH)2) solution, QAC diluted with 0.17% FdCa(OH)2 solution (Mix-500), sodium hypochlorite at 100 or 1,000 parts per million (ppm) of total chlorine (NaClO-100 or NaClO-1000, respectively). To efficiently inactivate MRV1 (≥ 3 log10 reductions), 0.17% FdCa(OH)2, Mix-500 and NaClO-1000 required 5 min, whereas it took 30 min for QAC-500. The number of MRV detections has decreased over time, after using Mix-500 for disinfection on the positive farm. These results suggest that different serotypes of MRVs are circulating among pigs, and that the occurrence of MRVs in the farms decreased consequent to more effective disinfection.

Electrolyzed hypochlorous acid water exhibits potent disinfectant activity against various viruses through irreversible protein aggregation

“…To address this, reverse osmosis treatment of HAWs was used to effectively remove coexisting Na + ions from the solution, resulting in the preparation of a highly purified slightly acidic hypochlorous acid water (Hp-SA-HAW), as detailed in section 2. In vitro experiments have demonstrated the effectiveness of HAW against various viruses ( Park et al, 2007 ; Hakim et al, 2015 ; Miyaoka et al, 2021 , 2023 ). However, the molecular mechanisms underlying the antiviral effects of HClO are still not fully understood.…”